2GB DDR2-800 Computer RAM

Expand the Memory Capacity in Your Computer with 2GB of PC2-6400 DDR2-800 RAM

PC2-6400 is a type of DDR2 RAM, or random-access memory, that holds all of the data currently being used by the processor. These 2GB modules will expand the number of programs and files you can have open at the same time.

Registered memory modules (also known as buffered memory) improve the stability and integrity of the memory when more modules are used than the system would typically be able to handle. An extra R in the name may identify partially buffered modules. If the module is fully buffered, then it is identified by an F or FB.

• Clock speed: This measures the speed of the internal memory arrays. PC2-6400 has a clock speed of 200 MHz.
• Data transfer rate: This refers to the total number of transfer operations that occur every second. It should not be confused with the actual amount of data being transferred. DDR2 memory can transfer data at four times the rate of the internal clock speed. Since the internal clock speed is 200 MHz, the data transfer rate would be 800. This is where the name DDR2-800 comes from.
• Data bandwidth: The data bandwidth is calculated by multiplying the data transfer rate by eight. That means the peak transfer rate of a PC2-6400 module is 6,400 megabytes per second as the name implies. Note that this is the maximum theoretical rate, and the actual real-world performance may be lower than the maximum limit.
• Latency: The latency measures the time it requires for the memory to perform certain actions. This may be measured in terms of minimum clock cycles and maximum clock cycles, and in the case of CAS latency, the precise number of clock cycles as agreed on between the memory controller and the memory itself.
• Error correction: ECC, or error-correcting code, modules have an entire data lane reserved to identify and correct errors in the data. Non-ECC modules do not have the ability.

Regarding the physical and electrical connection to the computer motherboard, there are two different types of modules. If you are using a desktop computer, then you will need a 240-pin DIMM. If you are using a laptop or other small form factor computer, then you will need a 200-pin SO-DIMM.

When mixing different modules, there are a few things to keep in mind. All DDR2 modules, regardless of clock speed or bandwidth, are generally compatible with each other although the computer will only operate at the speed of the slowest module. However, different generations of DDR modules are incompatible with each other. You cannot mix DDR2 with DDR3, for example, due to electronic and physical differences.